Cord locking mechanism for venetian blinds



Dec. 3, 1940. F. J. BURNS 2 com) LOCKINGMECHANISM FOR YENETIAN BLINDS Filed March 11, 1940 INVENTOR ATTORNEY Patented Dec. 3, 1940 UNITED STATES PATENT OFFICE Fred J. Burns, Saginaw, Mich assignor to The Columbia Mills, Inc., Saginaw, Mich, a corporation of New York Application Marehll, 1940, Serial No. 323,395 6 Claims. (o1. 156-17) The present invention relates to Venetian blinds and more particularly to means for locking and unlocking the slat elevating and supporting cords of such structure.

5 One of the prime objects of the invention is to provide a simple, inexpensive, highly eflicient, positive acting locking unit for the slat elevating and supporting cords of Venetian blinds.

Another object is, to provide a cord locking unit formed of stampings which can be assembled by the workman on a bench as a unit, so that it can be easily and quickly mounted in the head box of the blind.

A further object is to provide a simple, prac- 1 tical, and economical means for loosely holding the latching element in position in the unit.

A still further object is to provide a combination cord locking unit and tilt shaft support.

With the above and other objects in view,

20 the present invention consists in the combination and arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawing, and more particularly pointed out in the appended claims, it being understood that 25 changes may be made in the form, size, proportion, and minor details of construction, without departing from the spirit, or sacrificing any of the advantages of the invention.

In the drawing:

80 Fig. 1 is a fragmentary, part sectional, front elevational view of a Venetian blind head box showing my cord locking unit and tilt shaft support mounted in position therein.

Fig. 2 is a detail, perspective view showing the 85 various parts and the attaching means.

Fig. 3 is an end elevational view of the assembled unit.

Fig. 4 is a front elevational view, the housing being broken away to show the latch.

40 Referring now to the drawing in which I have shown one embodiment of my invention, the numeral 5 indicates the head box of a conventional Venetian blind in which my cord locking unit S is mounted. A tilt shaft 6 is mounted in 45 the box as usual and enlarged drums 1 are mounted on said shaft, ladder tape 8 being secured to said drums and project through openings 8 provided in the bottom of said box, this ladder tape supporting a plurality of blind slats 50 (not shown) in the usual manner.

Lifting cords l0 are connected to the bottom rail (not shown) of the blind as usual, thence leading upwardly through suitable openings provided in the head box, and thence being trained 55 over sheaves II which are mounted therein,

thence the cord leads through the locking unit S in a manner to be presently described.

The locking unit S comprises a tilt shaft supporting a bracket plate |2 preferably in the form of a stamping, the sides and bottom edges being 5 flanged as at l3 and I4, respectively, and openings l5 are provided therein to accommodate screws l6 for securing it in position. An angularly disposed opening I1 is provided in the vertical wall of the bracket plate l2, and spaced m apart notches I8 are provided in the lower marginal edge of said opening. Slits 9 are also provided in the plate at a point directly above the opening I! and the upper edge of said plate is shaped to form a key hole shaped open bearing for releasably supporting one end of the tilt shaft 6; a rectangular-shaped housing 2| forms a part of the unit and has open upper and lower ends 22 and 23 respectively, projecting ears 24 being formed integral with the edges of the 20 side walls of the housing and a vertical slot 25 is provided in each ear for engagement with the notches l8 provided in the lower marginal edge defining the opening A transversely disposed pin 26 is mounted in 25 the ear-shaped section 24 and a roller 21 is journaled on said pin and is freely rotatable. as the lift cord In travels thereover.

Pilot members 28 are formed integral with and on the upper edges of the side walls of the housing 2| and are received and accommodated in the slits I9 provided in the plate l2, and when in assembled relation, the ends of the pilot are bent over to rigidly secure the housing in position on the bracket.

A slotted opening 29 is provided in the end wall of the housing 2| and the shouldered end 30 of an angularly disposed latch member 3| is slidably mounted therein and normally projects beyond the end wall of said housing.

The latch member 3| is also formed of a stamping, the shouldered end 30 being upwardly bent with relation to the main body and the lower end section 32 is bent downwardly, the extreme lower end being serrated to form teeth 33 for engaging the lift cord when said cord is swung outwardly from the end of the blind and then released, the pull on the cords, due to the weight of the slats wedging the cord firmly between the latch and the wall of the bracket to hold it firmly in position.

To release the slats, the operator pulls downwardly on the cord ID to release the latch. The cord is then swung slightly inwardly and over the face of the blind and the blind slats can then an opening 35 provided in the flange ll of the bracket plate, thence being bent as shown, with the opposite end being accommodated in an opening 38 provided in the housing 2|, and this separator serves to prevent twisting and tangling of the lift cords, and which would otherwise prohibit successful operation of the locking mech-' anism.

I also wish to direct particular attention to the fact that the open bearing 20 permits easy assembly of the special shaped tilt shaft 8 and prevents accidental dislodging thereof during transit, and under normal operating conditions.

From the foregoing description, it will be obvious that I have perfected a simple, practical, and inexpensive article of manufacture, which can be readily and inexpensively stamped out of sheet metal, and can be quickly assembled on a bench and then mounted by inexpensive labor, and without sacrificing efliciency of the structure.

What I claim is:

l. A slat control unit for Venetian blinds comprising a bracket plate adapted to be secured in a head box, an angularly disposed opening therein, spaced slits above said opening, a housing mounted on said bracket plate and formed with projecting cars including slots adapted to engage the lower marginal edge of said opening, pilot sections on the edges of the housing and adapted to be accommodatedin said slits, a roller journaled on said ears, and a latch member loosely mounted in said housing for engaging and wedging a lift cord to hold it in adjusted position.

2. An automatic stop unit for Venetian blinds comprising a bracket plate, an opening therein to accommodate the blind lifting cord, a housing mounted on said plate and formed with ears including jaws adapted to fit over the marginal edge of the opening, a transversely disposed pin mounted on said ears, a roller journaled thereon, a latch mounted in said housing with its inner end toothed for engagement with a lift cord, and its opposite end shouldered and projecting through an opening in the end wall of the housmg.

3. A cord locking mechanism for Venetian blinds comprising a bracket plate provided with an angularly disposed opening therein, a housing mounted on the face of said plate and formed with projecting ears including jaws adapted to fit over the marginal edge of the opening, a'transversely disposed roller mounted on said ears, a toothed latch mounted in said housing and adapted to engage the lifting cords, and a separator spanning the lower end of said housing for separating said lift cords.

4. An automatic stop unit for Venetian blinds comprising a flanged, transversely disposed bracket plate provided with an angularly disposed opening therein, spaced apart slits in said plate above said opening, a U-shaped housing mounted on said plate and having projectiong ears formed integral with the legs of said housing, vertical slits in said ears and fitted over the lower marginal edge of the angularly disposed opening, a pin mounted in said ears, a roller journaled thereon, pilots on the legs of the housing adjacent the upper end thereof and'a'ccommodated in said slits, and a stamped latch mounted in said housing, the lower end being serrated to form teeth, the opposite end being shouldered andprojecting through a slit provided in the end wall of the housing.

5. An article of manufacture comprising a stamped, flanged, bracket plate provided-with a cord accommodating opening therein, spaced slits above said opening, an open bearing in the upper edge of said plate, a U-shaped stamped housing mounted on said plate, the edges being formed with projecting ears provided with vertically disposed slits therein and adapted to fit over the lower marginal edges of the cord accommodating opening, a roller journaled on said ears, pilots formed integral with the edges of the housing and accommodated in said slits, and a latch member located in said housing and formed with a shouldered upper end extending through a slit in the end wall of said housing, with its lower end bent downwardly and toothed for engaging with the lift cords of a blind.

6. A cord locking unit for Venetian blinds comprising a bracket plate, an open bearing in the upper edge thereof and adapted to releasably accommodate a tilt shaft, an opening in the body of the bracket plate, slits in the lower marginal edge thereof, a housing mounted on said plate and formed with ears including jaws'adapted to engage the slits in the lower marginal edge of said openings, a transversely disposed pin mounted on said ears, a roller journaled thereon, a latch swingingly mounted in said housing with its lower end toothed for engagement with the left. cord, and a separator mounted in said plate and releasably engaging said housing.

FRED J. BURNS. 

